From: Simon Horman <horms@kernel.org>
To: Pedro Tammela <pctammela@mojatatu.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com,
kuba@kernel.org, pabeni@redhat.com, jhs@mojatatu.com,
xiyou.wangcong@gmail.com, jiri@resnulli.us,
marcelo.leitner@gmail.com, vladbu@nvidia.com,
Jiri Pirko <jiri@nvidia.com>,
Victor Nogueira <victor@mojatatu.com>
Subject: Re: [PATCH net-next v3 1/5] rtnl: add helper to check if rtnl group has listeners
Date: Thu, 7 Dec 2023 20:59:56 +0000 [thread overview]
Message-ID: <20231207205956.GJ50400@kernel.org> (raw)
In-Reply-To: <20231206164416.543503-2-pctammela@mojatatu.com>
On Wed, Dec 06, 2023 at 01:44:12PM -0300, Pedro Tammela wrote:
> From: Jamal Hadi Salim <jhs@mojatatu.com>
>
> As of today, rtnl code creates a new skb and unconditionally fills and
> broadcasts it to the relevant group. For most operations this is okay
> and doesn't waste resources in general.
>
> When operations are done without the rtnl_lock, as in tc-flower, such
> skb allocation, message fill and no-op broadcasting can happen in all
> cores of the system, which contributes to system pressure and wastes
> precious cpu cycles when no one will receive the built message.
>
> Introduce this helper so rtnetlink operations can simply check if someone
> is listening and then proceed if necessary.
>
> Reviewed-by: Jiri Pirko <jiri@nvidia.com>
> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
> Signed-off-by: Victor Nogueira <victor@mojatatu.com>
> Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <horms@kernel.org>
next prev parent reply other threads:[~2023-12-07 21:00 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-06 16:44 [PATCH net-next v3 0/5] net/sched: conditional notification of events for cls and act Pedro Tammela
2023-12-06 16:44 ` [PATCH net-next v3 1/5] rtnl: add helper to check if rtnl group has listeners Pedro Tammela
2023-12-07 20:59 ` Simon Horman [this message]
2023-12-06 16:44 ` [PATCH net-next v3 2/5] rtnl: add helper to check if a notification is needed Pedro Tammela
2023-12-07 21:00 ` Simon Horman
2023-12-06 16:44 ` [PATCH net-next v3 3/5] rtnl: add helper to send if skb is not null Pedro Tammela
2023-12-07 21:00 ` Simon Horman
2023-12-06 16:44 ` [PATCH net-next v3 4/5] net/sched: act_api: conditional notification of events Pedro Tammela
2023-12-07 20:56 ` Simon Horman
2023-12-08 14:21 ` Pedro Tammela
2023-12-08 10:09 ` Jiri Pirko
2023-12-06 16:44 ` [PATCH net-next v3 5/5] net/sched: cls_api: " Pedro Tammela
2023-12-07 20:59 ` Simon Horman
2023-12-08 17:48 ` Pedro Tammela
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231207205956.GJ50400@kernel.org \
--to=horms@kernel.org \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=jhs@mojatatu.com \
--cc=jiri@nvidia.com \
--cc=jiri@resnulli.us \
--cc=kuba@kernel.org \
--cc=marcelo.leitner@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=pctammela@mojatatu.com \
--cc=victor@mojatatu.com \
--cc=vladbu@nvidia.com \
--cc=xiyou.wangcong@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).